1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * MPRLS0025PA - Honeywell MicroPressure pressure sensor series driver
5  * Copyright (c) Andreas Klinger <ak@it-klinger.de>
8  *  https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/
9  *    products/sensors/pressure-sensors/board-mount-pressure-sensors/
10  *    micropressure-mpr-series/documents/
11  *    sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
13  * 7-bit I2C default slave address: 0x18
46  * pressure = (press_cnt - outputmin) * scale + pmin
48  * * pressure	- measured pressure in Pascal
49  * * press_cnt	- raw value read from sensor
50  * * pmin	- minimum pressure range value of sensor (data->pmin)
51  * * pmax	- maximum pressure range value of sensor (data->pmax)
52  * * outputmin	- minimum numerical range raw value delivered by sensor
54  * * outputmax	- maximum numerical range raw value delivered by sensor
56  * * scale	- (pmax - pmin) / (outputmax - outputmin)
62  * * raw	- press_cnt
63  * * offset	- (-1 * outputmin) - pmin / scale
65  *                which reduces the offset to (-1 * outputmin)
148 	if (data->gpiod_reset) {  in mpr_reset()
149 		gpiod_set_value(data->gpiod_reset, 0);  in mpr_reset()
151 		gpiod_set_value(data->gpiod_reset, 1);  in mpr_reset()
156  * mpr_read_pressure() - Read pressure value from sensor via I2C
158  * @press: Output value read from sensor.
165  * Context: The function can sleep and data->lock should be held when calling it
167  * * 0		- OK, the pressure value could be read
168  * * -ETIMEDOUT	- Timeout while waiting for the EOC interrupt or busy flag is
171 static int mpr_read_pressure(struct mpr_data *data, s32 *press)  in mpr_read_pressure()  argument
173 	struct device *dev = &data->client->dev;  in mpr_read_pressure()
180 	reinit_completion(&data->completion);  in mpr_read_pressure()
182 	ret = i2c_master_send(data->client, wdata, sizeof(wdata));  in mpr_read_pressure()
188 		dev_err(dev, "received size doesn't fit - ret: %d / %u\n", ret,  in mpr_read_pressure()
190 		return -EIO;  in mpr_read_pressure()
193 	if (data->irq > 0) {  in mpr_read_pressure()
194 		ret = wait_for_completion_timeout(&data->completion, HZ);  in mpr_read_pressure()
197 			return -ETIMEDOUT;  in mpr_read_pressure()
203 			 * datasheet only says to wait at least 5 ms for the  in mpr_read_pressure()
205 			 * --> let's try it nloops (10) times which seems to be  in mpr_read_pressure()
206 			 *     quite long  in mpr_read_pressure()
209 			status = i2c_smbus_read_byte(data->client);  in mpr_read_pressure()
221 			return -ETIMEDOUT;  in mpr_read_pressure()
225 	ret = i2c_master_recv(data->client, buf, sizeof(buf));  in mpr_read_pressure()
231 		dev_err(dev, "received size doesn't fit - ret: %d / %u\n", ret,  in mpr_read_pressure()
233 		return -EIO;  in mpr_read_pressure()
242 		return -ETIMEDOUT;  in mpr_read_pressure()
245 	*press = get_unaligned_be24(&buf[1]);  in mpr_read_pressure()
247 	dev_dbg(dev, "received: %*ph cnt: %d\n", ret, buf, *press);  in mpr_read_pressure()
256 	complete(&data->completion);  in mpr_eoc_handler()
265 	struct iio_dev *indio_dev = pf->indio_dev;  in mpr_trigger_handler()
268 	mutex_lock(&data->lock);  in mpr_trigger_handler()
269 	ret = mpr_read_pressure(data, &data->chan.pres);  in mpr_trigger_handler()
273 	iio_push_to_buffers_with_timestamp(indio_dev, &data->chan,  in mpr_trigger_handler()
277 	mutex_unlock(&data->lock);  in mpr_trigger_handler()
278 	iio_trigger_notify_done(indio_dev->trig);  in mpr_trigger_handler()
284 	struct iio_chan_spec const *chan, int *val, int *val2, long mask)  in mpr_read_raw()
290 	if (chan->type != IIO_PRESSURE)  in mpr_read_raw()
291 		return -EINVAL;  in mpr_read_raw()
295 		mutex_lock(&data->lock);  in mpr_read_raw()
297 		mutex_unlock(&data->lock);  in mpr_read_raw()
303 		*val = data->scale;  in mpr_read_raw()
304 		*val2 = data->scale2;  in mpr_read_raw()
307 		*val = data->offset;  in mpr_read_raw()
308 		*val2 = data->offset2;  in mpr_read_raw()
311 		return -EINVAL;  in mpr_read_raw()
324 	struct device *dev = &client->dev;  in mpr_probe()
328 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE))  in mpr_probe()
329 		return dev_err_probe(dev, -EOPNOTSUPP,  in mpr_probe()
334 		return dev_err_probe(dev, -ENOMEM, "couldn't get iio_dev\n");  in mpr_probe()
337 	data->client = client;  in mpr_probe()
338 	data->irq = client->irq;  in mpr_probe()
340 	mutex_init(&data->lock);  in mpr_probe()
341 	init_completion(&data->completion);  in mpr_probe()
343 	indio_dev->name = "mprls0025pa";  in mpr_probe()
344 	indio_dev->info = &mpr_info;  in mpr_probe()
345 	indio_dev->channels = mpr_channels;  in mpr_probe()
346 	indio_dev->num_channels = ARRAY_SIZE(mpr_channels);  in mpr_probe()
347 	indio_dev->modes = INDIO_DIRECT_MODE;  in mpr_probe()
355 		ret = device_property_read_u32(dev, "honeywell,pmin-pascal",  in mpr_probe()
356 								&data->pmin);  in mpr_probe()
359 				"honeywell,pmin-pascal could not be read\n");  in mpr_probe()
360 		ret = device_property_read_u32(dev, "honeywell,pmax-pascal",  in mpr_probe()
361 								&data->pmax);  in mpr_probe()
364 				"honeywell,pmax-pascal could not be read\n");  in mpr_probe()
366 				"honeywell,transfer-function", &func);  in mpr_probe()
369 				"honeywell,transfer-function could not be read\n");  in mpr_probe()
370 		data->function = func - 1;  in mpr_probe()
371 		if (data->function > MPR_FUNCTION_C)  in mpr_probe()
372 			return dev_err_probe(dev, -EINVAL,  in mpr_probe()
373 				"honeywell,transfer-function %d invalid\n",  in mpr_probe()
374 								data->function);  in mpr_probe()
378 		data->pmin = 0;  in mpr_probe()
379 		data->pmax = 172369; /* 25 psi */  in mpr_probe()
380 		data->function = MPR_FUNCTION_A;  in mpr_probe()
383 	data->outmin = mpr_func_spec[data->function].output_min;  in mpr_probe()
384 	data->outmax = mpr_func_spec[data->function].output_max;  in mpr_probe()
387 	scale = div_s64(((s64)(data->pmax - data->pmin)) * NANO,  in mpr_probe()
388 						data->outmax - data->outmin);  in mpr_probe()
389 	data->scale = div_s64_rem(scale, NANO, &data->scale2);  in mpr_probe()
394 	offset = ((-1LL) * (s64)data->outmin) * NANO -  in mpr_probe()
395 			div_s64(div_s64((s64)data->pmin * NANO, scale), NANO);  in mpr_probe()
396 	data->offset = div_s64_rem(offset, NANO, &data->offset2);  in mpr_probe()
398 	if (data->irq > 0) {  in mpr_probe()
399 		ret = devm_request_irq(dev, data->irq, mpr_eoc_handler,  in mpr_probe()
400 				IRQF_TRIGGER_RISING, client->name, data);  in mpr_probe()
403 				"request irq %d failed\n", data->irq);  in mpr_probe()
406 	data->gpiod_reset = devm_gpiod_get_optional(dev, "reset",  in mpr_probe()
408 	if (IS_ERR(data->gpiod_reset))  in mpr_probe()
409 		return dev_err_probe(dev, PTR_ERR(data->gpiod_reset),  in mpr_probe()
410 						"request reset-gpio failed\n");  in mpr_probe()
450 MODULE_AUTHOR("Andreas Klinger <ak@it-klinger.de>");